At present, the above type of micromanipulators are typically used for example in the field of microscopes, the desired operating range for an operating instrument coupled with a micromanipulator being typically from 0,5 μm to 10 mm. With regard to all desired directions of motion for a micromanipulator, the solutions used today are primarily based on solutions implemented hydraulically or by using electric motors. One such solution is disclosed e.g. in Japanese patent publication 8323656, wherein the linear motion produced by electric motors applied in that context being transmitted from the rotating motion of a rotor by using a sufficiently high pitched rack-and-pinion arrangement. On the other hand, other solutions of the prior art make use of piezoelectric motors, which operate at ultrasonic frequency and which produce vibration wave as a result of activating electrically a piezoelectric material.
The type of solutions, described e.g. in the above-cited patent publication JP 8323656 and based, in principle, on highly conventional technology, have a drawback of not being able to provide integral units sufficiently compact in terms of operating several appliances. On the other hand, a drawback today in the latter type of piezoelectric motors operating at ultrasonic frequency concerns a sufficiently precise control of the motion produced thereby, which is why, at the present time, it is not yet possible in highly precise procedures to exploit this particular type of solutions with a sufficient reliability, especially in situations involving a change of load.
As a result of quite an undeveloped state of the art in current micromanipulator technology, the situation today is indeed such that, especially e.g. in microscope application, it is generally possible to use concurrently no more than two micromanipulators, which are positioned on the opposite sides of an operating target. Therefore, in the process of operating with various injectable media or providing a micromanipulator in different processes with various operating instruments, such as pipettes or needles, it is always necessary to disassemble some of the basic equipment when switching from one procedure to another, by additionally cleaning it, whenever necessary, before it can be replaced with a new medium or operating instrument needed next for each procedure. As a result, operating procedures based on the use of micromanipulators are today quite laborious and unnecessarily inefficient, because it is not possible to perform the work by utilizing a sufficient number of concurrently operable micromanipulators due to the problem with available space.
On the other hand, the published Japanese application 09-267278 and the corresponding published European application 09267278 disclose a micromanipulator construction, wherein, particularly for providing a substantially elongated micromanipulator structure, one or more of its actuators enabling the positioning/localization of an operating instrument, for affecting at least one of its desired directions of motion, are implemented in the way of piezoelectric benders. However, the solution disclosed in this context is based on piezoelectric benders connected in parallel on top of the external surface of the flexible operating frame of a micromanipulator, wherein the bending or deflection is a result of rotations/elongations of benders on the opposite sides due to potential differences. Thus, the solution requires extremely precise mathematical modelling because, for example, a deflection, occurring in just a single direction, necessitates a simultaneous control over all parallel-connected benders for providing a desired displacement or motion. On the other hand, an operating instrument, such as the tip of an injection needle, can be adapted to affect an axial motion by providing all benders with the same potential difference. In this case, the bender construction is further coupled pivotally with its actuator and, hence, each desired position for an operating instrument is extremely difficult to set in practice in a reliable and sufficiently accurate manner. Thus, only relatively small motions can be reliably provided by a solution of this particular type, especially in axial direction.